Currently I’m using Joplin with Syncthing-backed file system synchronization. I’m pretty pleased with it, as I do like tagging- and Markdown-based systems.
I plan to upgrade to server-based synchronization, but before doing that, however, I wanted to see what other people are using.
Edit: So far I see a slight favor towards Joplin and Logseq, but I totally didn’t expect (and appreciate) getting so many different answers.
orgmode with neovim on PC and orgzly on phone. syncing with syncthing
Edit: I’m actually using orgzly revived, a community maintained version of orgzly, since orgzly is no longer mantained
For anyone who is interested in note taking in your everyday editor like vim or emacs, orgmode is an emacs tool (in neovim there is a clone plugin) for note taking, todos, agendas, etc. It uses a format similar to markdown, and a good part is that with the orgzly app you receive notifications for your events. So basically you can use orgmode as a calendar as well (I do!).